Phospor, arsenic and antimony compounds based upon diaryl-anellated diaryl-anellated bicyclo&#39;2.2.n! parent substances and catalysts containing same

ABSTRACT

Novel compounds of phosphorus, of arsenic and of antimony can be used as ligands to form complexes of metals of transition group VIII which can be used in catalysts for hydroformylation, hydrocyanation, carbonylation, hydrogenations, oligomerization and polymerization of olefins and for metathesis.

[0001] The present invention relates to compounds of phosphorus, ofarsenic and of antimony, to a process for preparing them and to acatalyst comprising at least one complex of a metal of transition groupVIII with such a compound as ligand. The invention further relates tothe use of these catalysts for hydroformylation, hydrocyanation,carbonylation, hydrogenation, olefin oligomerization and olefinpolymerization and for metathesis.

[0002] Hydroformylation or the oxo process is an important industrialprocess employed for preparing aldehydes from olefins, carbon monoxideand hydrogen. These aldehydes can, if desired in the same process step,be hydrogenated by means of hydrogen to form the corresponding oxoalcohols. The reaction itself is strongly exothermic and generallyproceeds under superatmospheric pressure at elevated temperatures in thepresence of catalysts. Catalysts used are Co, Rh, Ir, Ru, Pd or Ptcompounds or complexes which may be modified by N- or P-containingligands to influence the activity and/or selectivity. Thehydroformylation reaction results in formation of mixtures of isomericaldehydes because CO can add onto either of the two carbon atoms of adouble bond. In addition, double bond isomerization can also occur. Inthese isomeric mixtures, the n-aldehyde frequently predominates over theisoaldehyde and, owing to the significantly greater industrialimportance of the n-aldehydes, optimization of the hydroformylationcatalysts to achieve a greater n-selectivity is sought.

[0003] It is known that phosphorus-costaining ligands can be used in thelow-pressure rhodium-catalyzed hydroformylation to stabilize and/oractivate the catalyst metal. Examples of suitable phosphorus-containingligands are phosphines, phosphinites, phosphonites, phosphites,phosphoramidites, phospholes and phosphabenzenes. The most widespreadligands at present are triarylphosphines, e.g. triphenylphosphine andsulfonated triphenylphosphine, since these have sufficient stabilityunder the reaction conditions. However, these ligands have thedisadvantage that, in general, only very high ligand excesses givesatisfactory yields, in particular of linear aldehydes. On the otherhand, chelating phosphites give high yields of linear aldehydes even atgenerally very low ligand excesses, but these ligands have thedisadvantage of a low stability which, combined with their relativelyhigh acquisition costs, has an adverse effect on the economics of thehydroformylation process.

[0004] Beller et al., Journal of Molecular Catalysis A, 104 (1995),pages 17-85, describe rhodium-containing, phosphine-modified catalystsfor the hydroformylation of low-boiling olefins.

[0005] DE-A-196 523 50 describes catalysts based on4,5-diphosphinoacridine ligands. These are suitable for catalyzingcarbon monoxide converting by means of the water gas equilibrium.Furthermore, they are said to be suitable for catalyzinghydroformylation, carbonylation, carboxylation, hydrogenation,hydrocyanation, hydrosilylation, polymerization, isomerization, crosscoupling and metathesis. The latter is not evidenced by examples in thedocument. Disadvantages of these ligands are their complicatedmultistage synthesis and the angle of bite which is unfavorable forchelating rhodium.

[0006] In Tetrahedron Letters, volume 34, No. 13, pages 2107ff (1993),in Tetrahedron Letters, volume 36, No. 1, pages 75ff (1995) and in Chem.Ber. 124, page 1705ff (1991), Haenel et al. describe the synthesis ofbis(diphenylphosphino) chelates based on anthracene, dibenzofuran,dibenzothiophene and xanthene parent molecules. The use of thesecompounds in catalysis is not described. Disadvantages of thesecompounds are their multistage synthesis and, once again, the angle ofbite which is unfavorable for chelating rhodium.

[0007] In Organometallics 1995, 14, page 3081ff, van Leeuwen et al.describe the synthesis of chelating phosphines based on xanthene asparent molecule and their use as cocatalysts in the low-pressurerhodium-catalyzed hydroformylation of α-olefins. Disadvantages of theseligands are the complicated synthesis of the parent xanthene structureand the necessity of using sensitive organometallic compounds in thesynthesis. Hydroformylation processes using catalysts on the basis ofthese ligands are therefore economically disadvantageous.

[0008] The catalytic hydrocyanation of olefins for the preparation ofnitriles likewise has great industrial importance.

[0009] “Applied Homogeneous Catalysis with Organometallic Compounds”,volume 1, VCH Weinheim, page 465ff, describes the heterogeneously andhomogeneously catalyzed addition of hydrogen cyanide onto olefins ingeneral terms. Catalysts used are, in particular, catalysts based onphosphine, phosphite and phosphonite complexes of nickel and palladium.

[0010] In Organometallics 1984, 3, page 33ff, C. A. Tolman et al.describe the catalytic hydrocyanation of olefins in the presence ofnickel(0) phosphite complexes taking specific account of the effect ofLewis acids on the hydrogen cyanide addition.

[0011] Advances in Catalysis, volume 33, 1985, Academic Press Inc., page1ff, gives an overview of the homogeneously nickel-catalyzedhydrocyanation of olefins. Catalysts used are nickel(0) complexes havingphosphine and phosphite ligands.

[0012] None of the abovementioned literature references describescatalysts, for example hydroformylation catalysts or hydrocyanationcatalysts, based on phosphorus-containing diaryl-fused bicyclo [2.2.n]structures.

[0013] It is an object of the present invention to provide new compoundsof phosphorus, of arsenic and of antimony and also a process forpreparing them. These compounds should preferably be suitable as ligandsfor transition metal complexes of metals of transition group VIII so asto provide novel catalysts based on these metal complexes. These ligandsshould preferably be easy to prepare and/or their complexes should bevery stable under the reaction conditions of the reactions to becatalyzed. The catalysts should preferably be suitable forhydroformylation, hydrocyanation or carbonylation and have a goodcatalytic activity.

[0014] We have found that this object is achieved by compounds ofphosphorus, of arsenic and of antimony based on diaryl-fused bicyclo[2.2.n] structures which are suitable as ligands for transition metalcomplexes of metals of transition group VIII.

[0015] The present invention accordingly provides compounds of theformula I

[0016] where

[0017] A¹ and A² are each, independently of one another, B, N, P or CR⁵,where R⁵ is hydrogen, alkyl, cycloalkyl, aryl or heteroaryl,

[0018] X is O, S, NR^(a) or a divalent bridging group, where R^(a) ishydrogen, alkyl, cycloalkyl or aryl,

[0019] Y¹ and Y² are, independently of one another, radicals containingat least one phosphorus, arsenic or antimony atom, where the phosphorus,arsenic or antimony atom is bound directly or via an oxygen atom to thephenyl ring in formula I,

[0020] R¹, R², R³ and R⁴ are each, independently of one another,hydrogen, alkyl, cycloalkyl, aryl, alkoxy, halogen, NE¹E²,alkylene-NE¹E², trifluoromethyl, nitro, alkoxycarbonyl or cyano, whereE¹ and E² are identical or different and are each alkyl, cycloalkyl oraryl.

[0021] For the purposes of the present invention, the expression ‘alkyl’encompasses both straight-chain and branched alkyl groups. Preference isgiven to straight-chain or branched C₁-C₈-alkyl groups, more preferablyC₁-C₆-alkyl groups and particularly preferably C₁-C₄-alkyl groups.Examples of alkyl groups are, in particular, methyl, ethyl, propyl,isopropyl, n-butyl, 2-butyl, sec-butyl, tert-butyl, n-pentyl, 2-pentyl,2-methylbutyl, 3-methylbutyl, 1,2-dimethylpropyl, 1,1-dimethylpropyl,2,2-dimethylpropyl, 1-ethylpropyl, n-hexyl, 2-hexyl, 2-methylpentyl,3-methylpentyl, 4-methylpentyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl,2,3-dimethylbutyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl,3,3-dimethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl,1-ethylbutyl, 2-ethylbutyl, 1-ethyl-2-methylpropyl, n-heptyl, 2-heptyl,3-heptyl, 2-ethylpentyl, 1-propylbutyl, octyl.

[0022] Cycloalkyl is preferably a C₅-C₇-cycloalkyl group such ascyclopentyl, cyclohexyl or cycloheptyl.

[0023] If the cycloalkyl group is substituted, it preferably has 1, 2,3, 4 or 5, in particular 1, 2 or 3, substituents selected from amongalkyl, alkoxy and halogen.

[0024] Aryl is preferably phenyl, tolyl, xylyl, mesityl, naphthyl,anthracenyl, phenanthrenyl or naphthacenyl, in particular phenyl ornaphthyl.

[0025] Substituted aryl radicals preferably have 1, 2, 3, 4 or 5, inparticular 1, 2 or 3, substituents selected from among alkyl, alkoxy,carboxyl, carboxylate, trifluoromethyl, —SO₃H, sulfonate, NE¹E²,alkylene-NE¹E², nitro, cyano and halogen. A preferred substituted arylradical is pentafluorophenyl.

[0026] Heteroaryl is preferably pyrrolyl, pyrazolyl, imidazolyl,indolyl, carbazolyl, pyridyl, quinolinyl, acridinyl, pyridazinyl,pyrimidinyl or pyrazinyl.

[0027] Substituted heteroaryl radicals preferably have 1, 2 or 3substituents selected from among alkyl, alkoxy, —SO₃H, sulfonate, NE¹E²,alkylene-NE¹E², trifluoromethyl and halogen.

[0028] What has been said above regarding alkyl, cycloalkyl and arylradicals applies analogously to alkoxy, cycloalkyloxy and aryloxyradicals.

[0029] The groups NE¹E² are preferably N,N-dimethylamino,N,N-diethylamino, N,N-dipropylamino, N,N-diisopropylamino,N,N-di-n-butylamino, N,N-di-t-butylamino, N,N-dicyclohexylamino orN,N-diphenylamino.

[0030] Halogen is fluorine, chlorine, bromine or iodine, preferablyfluorine, chlorine and bromine.

[0031] For the purposes of the present invention, carboxylate ispreferably a derivative of a carboxylic acid function, in particular ametal carboxylate, a carboxylic ester function or a carboxamidefunction, particularly preferably a carboxylic ester function. Theseinclude, for example, esters of C₁-C₄-alkanols such as methanol,ethanol, n-propanol, isopropanol, n-butanol, sec-butanol ortert-butanol.

[0032] A¹ and A² are preferably selected from among N and CR⁵. If R⁵ isalkyl, cycloalkyl, aryl or hetaryl, these radicals can have at least onesubstituent. Preferred substituents of the radicals R⁵ are polar(hydrophilic) groups. The polar groups are preferably selected fromamong COOR^(k), COO⁻M⁺, SO₃R^(k), SO₃ ⁻M⁺, NE³E⁴, NE³E⁴E⁵⁺X⁻, OR^(f),SR^(f), (CHR¹CH₂O)_(x)R^(k) and (CH₂CH₂N(E³))_(x)R^(k), where R^(k), E³,E⁴ and E⁵ are each identical or different radicals selected from amonghydrogen, alkyl, cycloalkyl and aryl; R¹ is hydrogen, methyl or ethyl;M⁺ is a cation such as Li⁺, Na⁺, K⁺, NH₄ ⁺; X⁻ is an anion such as Cl⁻or Br⁻, and x is an integer from 1 to 120.

[0033] If R⁵ is a polymeric support which may be bound via a spacergroup, then the support is preferably selected from among styrenehomopolymers and copolymers, in particular styrene-divinylbenzenecopolymers (Merrifield resins), polyamides, aminomethylated polystyreneresins, etc. Suitable spacers include alkylene chains which maybeinterrupted by one or more nonadjacent heteroatoms such as O, S, NR^(x),where R^(x) is hydrogen, alkyl, cycloalkyl or aryl. The alkylene chainsmay also bear functional groups such as ester and/or amino groups.

[0034] In a preferred embodiment, R⁵ is hydrogen or substituted orunsubstituted C₁-C₈-alkyl.

[0035] Y¹ and Y² are preferably radicals containing a phosphorus atom,in particular radicals of the formulae PR⁶R⁷, P(OR⁶)R⁷, P(OR⁶)(OR⁷),OPR⁶R⁷, OP(OR⁶)R⁷ and OP(OR⁶)(OR⁷), where

[0036] R⁶ and R⁷ are each, independently of one another, alkyl,cycloalkyl, aryl or heteroaryl which may bear one, two or threesubstituents selected from among alkyl, cycloalkyl, aryl, alkoxy,cycloalkyloxy, aryloxy, halogen, trifluoromethyl, nitro, cyano,carboxyl, carboxylate, acyl, —SO₃H, sulfonate, NE¹E² and alkylene-NE¹E²,where E¹ end E² are identical or different and are selected from amongalkyl, cycloalkyl and aryl, or

[0037] R⁶ and R⁷ together with the phosphorus atom and, if present, theoxygen atom(s) to which they are bound form a 5- to 8-memberedheterocycle which may additionally be fused with one, two or threecycloalkyl, aryl and/or heteroaryl rings, where the fused-on groups mayeach bear, independently of one another, one, two, three or foursubstituents selected from among alkyl, alkoxy, halogen, nitro, cyano,carboxyl carboxylate and —SO₃H, sulfonate, NE¹E² and alkylene-NE¹E² andwhere the heterocycle may additionally contain one or two heteroatoms(s)selected from among N, O and S.

[0038] The bridging group X is preferably a divalent bridging grouphaving from 1 to 15 atoms in the chain between the flanking bonds.

[0039] X is preferably a C₁-C₁₀-alkylene bridge which may contain one,two, three or four double bonds and/or may bear one, two, three or foursubstituents selected from among alkyl, alkoxy, halogen, nitro, cyano,carboxyl, carboxylate, cycloalkyl and aryl, where the aryl substituentmay additionally bear one, two or three substituents selected from amongalkyl, alkoxy, halogen, trifluoromethyl, —SO₃H, sulfonate, NE¹E²,alkylene-NE¹E², nitro, alkoxycarbonyl and cyano, and/or the alkylenebridge X may be interrupted by one, two or three nonadjacent,substituted or unsubstituted heteroatoms, and/or the alkylene bridge Xmay be fused with one, two or three aryl and/or heteroaryl rings, wherethe fused-on aryl and heteroaryl groups may each bear one, two or threesubstituents selected from among alkyl, cycloalkyl, aryl, alkoxy,cycloalkoxy, aryloxy, acyl, halogen, trifluoromethyl, —SO₃H, sulfonate,nitro, cyano, carboxyl, alkoxycarbonyl, NE¹E² and alkylene-NE¹E², whereE¹ and E² may be identical or different and are each alkyl, cycloalkylor aryl.

[0040] The radical X is particularly preferably a C₁-C₈-alkylene bridgewhich, depending on the number of carbon atoms, is fused with 1, 2 or 3aryl rings and/or can have 1, 2, 3 or 4 substituents selected from amongalkyl, cycloalkyl and substituted or unsubstituted aryl, and/or canadditionally be interrupted by 1, 2 or 3 unsubstituted or substitutedheteroatoms.

[0041] The fused-on aryls of the radicals X are preferably benzene ornaphthalene, in particular benzene. Fused-on benzene rings arepreferably unsubstituted or have 1, 2 or 3, in particular 1 or 2,substituents selected from among alkyl, alkoxy, halogen, SO₃H,sulfonate, NE¹E², alkylene-NE¹E², trifluoromethyl, nitro, carboxyl,alkoxycarbonyl and cyano. Fused-on naphthalenes are preferablyunsubstituted or have, in the ring which is not fused-on and/or in thefused-on ring, in each case 1, 2 or 3, in particular 1 or 2, of thesubstituents specified above for the fused-on benzene rings. Thesesubstituents are then preferably alkyl or alkoxycarbonyl. Alkyl assubstituent on the fused-on aryls is preferably C₁-C₄-alkyl and inparticular methyl, isopropyl or tert-butyl. Alkoxy is preferablyC₁-C₄-alkoxy and in particular methoxy. Alkoxycarbonyl is preferablyC₁-C₄-alkoxycarbonyl. Halogen is particularly preferably fluorine orchlorine.

[0042] If the alkylene bridge of the radical X is interrupted by 1, 2 or3 unsubstituted or substituted heteroatoms, the heteroatoms arepreferably selected from among O, S and NR¹⁷, where R¹⁷ is alkyl,cycloalkyl or Aryl.

[0043] If the alkylene bridge of the radical X is substituted, it has 1,2, 3 or 4 substituents which is/are preferably selected from amongalkyl, cycloalkyl and aryl, where the aryl substituent may additionallybear 1, 2 or 3 substituents selected from among alkyl, alkoxy, halogen,—SO₃H, sulfonate, NE¹E², alkylene-NE¹E², trifluoromethyl, nitro,alkoxycarbonyl and cyano. The substituents of the alkylene bridge X arepreferably selected from among methyl, ethyl, n-propyl, isopropyl,n-butyl, sec-butyl, tert-butyl, phenyl, p-(C₁-C₄-alkyl)phenyl,preferably p-methylphenyl, p-(C₁-C₄-alkoxy)phenyl, preferablyp-methoxyphenyl, p-halophenyl, preferably p-chlorophenyl, andp-trifluoromethylphenyl.

[0044] In a preferred embodiment, X is a nonfused C₁-C₃-alkylene bridge,where C₂- and C₃-alkylene bridges may contain a double bond. Inparticular, the radicals X have 1, 2, 3 or 4 substituents selected fromamong methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl,tert-butyl, halogen and alkyloxycarbonyl.

[0045] In a further preferred embodiment, X is selected from amongradicals of the formulae II.1 to II.10

[0046] where

[0047] Z is O, S or NR¹⁶, where

[0048] R¹⁶ is alkyl, cycloalkyl or aryl,

[0049] or Z is a C₁-C₃-alkylene bridge which may contain a double bondand/or bear an alkyl, cycloalkyl or aryl substituent, where the arylsubstituent may bear one, two or three substituents specified for aryl,

[0050] or Z is a C₂-C₃-alkylene bridge which is interrupted by O, S orNR¹⁶,

[0051] R⁸, R⁸′, R⁹, R⁹′, R¹⁰, R¹¹, R¹², R¹³, R¹⁴ and R¹⁵ are each,independently of one another, hydrogen, alkyl, cycloalkyl, aryl, alkoxy,halogen, SO₃H, sulfonate, NE¹E², alkylene-NE¹E², trifluoromethyl, nitro,alkoxycarbonyl, carboxyl or cyano.

[0052] X is preferably a radical of the formulae II.1 or II.2, where R⁸and R⁹ are, independently of one another hydrogen orC₁-C₄-alkoxycarbonyl, in particular COOEt. Particularly preferably, R⁸and R⁹ are both hydrogen.

[0053] X is preferably a radical of the formula II.3, where R⁸ and R⁹are, independently of one another, hydrogen or C₁-C₄-alkyl.

[0054] In the formula I, it is preferred that one of the radicals Y¹ andY² or both the radicals Y¹ and Y² are selected from among radicals ofthe formulae PR⁶R⁷, P(OR⁶)R⁷, P(OR⁶)(OR⁷), OPR⁶R⁷, OP(OR⁶)R⁷ andOP(OR⁶)(OR⁷) in which R⁶ and R⁷ are selected from among C₁-C₆-alkyl, inparticular ethyl, n-propyl, isopropyl and tert-butyl, C₅-C₇-cycloalkyl,in particular cyclohexyl, aryl, in particular phenyl and hetaryl, inparticular pyrrolyl, pyrazolyl, imidazolyl, indolyl and carbazolyl.

[0055] In the formula I, preference is given to one of the radicals Y¹or Y² or both radicals Y¹ and Y² being selected from among radicals ofthe formulae PR⁶R⁷, P(OR⁶)R⁷, P(OR⁶)(OR⁷), OPR⁶R⁷, OP(OR⁶)R⁷ andOP(OR⁶)(OR⁷), where R⁶ and R⁷ together with the phosphorus atom and, ifpresent, the oxygen atom(s) to which they are bound form a 5- to8-membered heterocycle which may additionally be fused with one, two orthree cycloalkyl, aryl and/or heteroaryl rings, where the fused-ongroups may each bear, independently of one another, one, two, three orfour substituents selected from among alkyl, alkoxy, halogen, nitro,cyano, carboxyl, SO₃H, sulfonate, NE¹E², alkylene-NE¹E² and carboxylate.

[0056] The radicals Y¹ and y² are preferably selected from amongphosphine, phosphinite, phosphonite and/or phosphite groups of theformula III

[0057] where

[0058] x, y and z are each, independently of one another, 0 or 1 and

[0059] D together with the phosphorus atom and, if x and/or y are 1, theoxygen atom(s) to which it is bound forms a 5- to 8-membered heterocyclewhich may additionally be fused with one, two or three cycloalkyl, aryland/or heteroaryl rings, where the fused-on groups may each bear,independently of one another, one, two, three or four substituentsselected from among alkyl, alkoxy, halogen, SO₃H, sulfonate, NE¹E²,alkylene-NE¹E², nitro, cyano, carboxyl and carboxylate.

[0060] The radical D is preferably a C₂-C₇-alkylene bridge which isfused with 1, 2 or 3 aryl rings and may additionally bear a substituentselected from among alkyl, cycloalkyl and substituted or unsubstitutedaryl and/or may additionally be interrupted by an unsubstituted orsubstituted heteroatom.

[0061] The fused-on aryls of the radicals D are preferably benzene ornaphthalene. Fused-on benzene rings are preferably unsubstituted or have1, 2 or 3, in particular 1 or 2, substituents selected from among alkyl,alkoxy, halogen, SO₃H, sulfonate, NE¹E², alkylene-NE¹E²,trifluoromethyl, nitro, carboxyl, alkoxycarbonyl and cyano. Fused-onnaphthalenes are preferably unsubstituted or have, in the ring which isnot fused on and/or in the fused-on ring, in each case 1, 2 or 3, inparticular 1 or 2, of the substituents specified above for the fused-onbenzene rings. Fused-on naphthalenes which are substituted in thefused-on ring preferably have a substituent in the ortho positionrelative to the phosphonite group. This is then preferably alkyl oralkoxycarbonyl. Alkyl as substituent of the fused-on aryls is preferablyC₁-C₄-alkyl and in particular methyl, isopropyl or tert-butyl. Alkoxy ispreferably C₁-C₄-alkoxy and in particular methoxy. Alkoxycarbonyl ispreferably C₁-C₄-alkoxycarbonyl. Halogen is particularly preferablyfluorine or chlorine.

[0062] If the C₂-C₇-alkylene bridge of the radical D is interrupted by1, 2 or 3 unsubstituted or substituted heteroatoms, these are selectedfrom among O, S and NR¹⁸, where R¹⁸ is alkyl, cycloalkyl or aryl. TheC₂-C₇-alkylene bridge of the radical D is preferably interrupted by anunsubstituted or substituted heteroatom.

[0063] If the C₂-C₇-alkylene bridge of the radical D is substituted, ithas 1, 2 or 3 substituents, in particular 1 substituent, which is/areselected from among alkyl, cycloalkyl and aryl, where the arylsubstituent may bear 1, 2 or 3 of the substituents specified for aryl.The alkylene bridge D preferably has a substituent selected from amongmethyl, ethyl, isopropyl, phenyl, p-(c₁-C₄-alkyl)phenyl, preferablyp-methylphenyl, p-(C₁-C₄-alkoxy)phenyl, preferably p-methoxyphenyl,p-halophenyl, preferably p-chlorophenyl, and p-trifluoromethylphenyl.

[0064] The radical D is preferably a C₄-C₇-alkylene bridge which is, asdescribed above, fused and/or substituted and/or interrupted byunsubstituted or substituted heteroatoms. In particular, the radical Dis a C₄-C₅-alkylene bridge which is fused with one or two phenyl and/ornaphthyl groups, where the phenyl or naphthyl groups may bear 1, 2 or 3,in particular 1 or 2, of the abovementioned substituents.

[0065] The radical D (i.e. R⁶ and R⁷ together) together with thephosphorus atom and, if present, the oxygen atom(s) to which it is boundpreferably forms a 5- to 8-membered heterocycle, where D (R⁶ and R⁷together) is a radical selected from among the radicals of the formulaeII.5 to II.9,

[0066] where

[0067] Z is O, S or NR¹⁶, where

[0068] R¹⁶ is alkyl, cycloalkyl or aryl,

[0069] or Z is a C₁-C₃-alkylene bridge which may contain a double bondand/or bear an alkyl, cycloalkyl or aryl substituent, where the arylsubstituent may bear one, two or three substituents specified for aryl,

[0070] or Z is a C₂-C₃-alkylene bridge which is interrupted by O, S orNR¹⁶,

[0071] R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴ and R¹⁵ are each, independentlyof one another, hydrogen, alkyl, cycloalkyl, aryl, alkoxy, halogen,SO₃H, sulfonate, NE¹E², alkylene-NE¹E², trifluoromethyl, nitro,alkoxycarbonyl, carboxyl or cyano.

[0072] D is preferably a radical of the formula II.5 in which R⁸ and R⁹are each hydrogen.

[0073] D is preferably a radical of the formula II.6a

[0074] where

[0075] R⁸ is hydrogen, C₁-C₄-alkyl, SO₃H, sulfonate, NE¹E²,alkylene-NE¹E², preferably hydrogen or C₁-C₄-alkyl, in particularmethyl, isopropyl or tert-butyl,

[0076] R⁹ is hydrogen, C₁-C₄-alkyl, preferably methyl, isopropyl ortert-butyl, C₁-C₄-alkoxy, preferably methoxy, fluorine, chlorine ortrifluoromethyl. R⁹ can also be SO₃H, sulfonate, NE¹E² oralkylene-NE¹E².

[0077] D is preferably a radical of the formula II.7a

[0078] where

[0079] R⁸ and R⁹ have the meanings given under the formula II.6a,

[0080] R¹⁹ is hydrogen, C₁-C₄-alkyl, preferably methyl or ethyl, phenyl,p-(C₁-C₄-alkoxy)phenyl, preferably p-methoxyphenyl, p-fluorophenyl,p-chlorophenyl or p-(trifluoromethyl)phenyl.

[0081] D is preferably a radical of the formula II.8, in which R⁸, R⁹,R¹⁰, R¹¹, R¹², R¹³, R¹⁴ and R¹⁵ are each hydrogen.

[0082] D is preferably a radical of the formula II.8 in which R⁸, R⁹,R¹⁰, R¹¹, R¹³ and R¹⁵ are each hydrogen and the radicals R¹² and R¹⁴ areeach, independently of one another, alkoxycarbonyl, preferablymethoxycarbonyl, ethoxycarbonyl, n-propyloxycarbonyl orisopropyloxycarbonyl. In particular, the radicals R¹² and R¹⁴ arelocated in the ortho position relative to the phosphorus atom or oxygenatom.

[0083] D is preferably a radical of the formula II.9 in which R⁸, R⁹,R¹⁰, R¹¹, R¹², R¹³, R¹⁴ and R¹⁵ are each hydrogen and Z is CR¹⁹, whereR¹⁹ is as defined above.

[0084] D is preferably a radical of the formula II.9 in which R⁸, R⁹,R¹⁰, R¹¹, R¹³ and R¹⁵ are each hydrogen, Z is CR¹⁹ and the radicals R¹²and R¹⁴ are each, independently of one another, alkoxycarbonyl,preferably methoxycarbonyl, ethoxycarbonyl, n-propyloxycarbonyl orisopropyloxycarbonyl. In particular, the radicals R¹² and R¹⁴ arelocated in the ortho position relative to the phosphorus atom or oxygenatom.

[0085] In particular, the phosphorus-containing compound is selectedfrom among compounds of the formulae I.i to I.v.

[0086] where

[0087] R^(a) is selected from among C₁-C₆-alkyl, C₁-C₆-alkoxy,C₅-C₇-cycloalkoxy, phenyl, phenoxy and pentafluorophenyl, where thephenyl- and phenoxy radicals may bear a substituent selected from amongcarboxyl, carboxylate, —SO₃H and sulfonate,

[0088] R^(b), R^(b)′, R^(c) and R^(c)′ are selected independently fromamong hydrogen, C₁-C₆-alkyl, C₁-C₆-alkoxy, C₁-C₆-alkoxycarbonyl andaryl,

[0089] R^(d) and R^(e) are selected independently from among hydrogenand C₁-C₆-alkyl,

[0090] R^(f) and R^(g) are selected independently from among hydrogen,C₁-C₆-alkyl and C₁-C₆-alkoxy, and

[0091] A¹ and A² are each, independently of one another, N or CR⁵, whereR⁵ is hydrogen or C₁-C₈-alkyl.

[0092] The radicals R^(b), R^(b)′, R^(c) and R^(c)′ are preferablyselected from among hydrogen, methyl, ethyl, n-propyl, isopropyl,n-butyl, tert-butyl, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy,tert-butoxy, methoxycarbonyl, ethoxycarbonyl and phenyl.

[0093] Examples of phosphorous-containing compounds preferred accordingto the present invention are shown below.

[0094] The compounds of the present invention are generally prepared by[4+2]-cycloaddition reactions, in the case of the compounds I based onbicyclo[2.2.2] parent structures preferably by [4+2]-cycloaddition(Diels-Alder reaction), of appropriately substituted anthracenes,acridines or analogous hetero compounds as diene components withdienophiles capable of forming the bridging groups X.

[0095] The present invention therefore also provides a process forpreparing compounds of the formula I in which X is a radical of theformulae II.1, II.2, II.3 or II.4

[0096] where

[0097] R⁸, R⁸′, R⁹, R⁹′, R¹⁰ and R¹¹ are each, independently of oneanother, hydrogen, alkyl, cycloalkyl, aryl, alkoxy, halogen, SO₃H,sulfonate, NE¹E², alkylene-NE¹E², trifluoromethyl, nitro,alkoxycarbonyl, carboxyl or cyano,

[0098] by reacting a compound of the formula I.1

[0099] where

[0100] A¹ and A² are each, independently of one another, B, N, P or CR⁵,where R⁵ is hydrogen, alkyl, cycloalkyl, aryl, heteroaryl or a polymericsupport which may be bound via a spacer group

[0101] Y^(a) and Y^(b) are each, independently of one another, radicalsY¹ or y² as defined above

[0102] or Y^(a) and Y^(b) are each, independently of one another,halogen, OH, OC(O)CF₃ or SO₃Me where Me=hydrogen, Li, Na or K, whereY^(a) and/or Y^(b) can also be hydrogen if in each case one of theradicals R² and/or R⁴ is an alkoxy group which is located in the orthoposition of Y^(a) and/or Y^(b),

[0103] R¹, R², R³ and R⁴ are each, independently of one another,hydrogen, alkyl, cycloalkyl, aryl, alkoxy, halogen, trifluoromethyl,nitro, alkoxycarbonyl or cyano,

[0104] with a compound selected from among compounds of the formulaeII.a, II.b, II.c or II.d

[0105] or a precursor of a compound of the formula II.c or II.d in a[4+2]-cycloaddition (Diels-Alder reaction) and,

[0106] if desired, functionalizing radicals Y^(a) and/or Y^(b) to formradicals Y¹ and/or y².

[0107] To prepare the compounds of the formula I.1, in which R¹, R², R³and R⁴ are as defined above, which are used according to the presentinvention, it is possible, for example, to reduce a1,8-dihalogen-substituted anthraquinone of the formula III, in whichY^(a) and Y^(b) have one of the above meanings and are, for example,halogen, in particular chlorine or bromine, according to scheme 1 below

[0108] to give a compound of the formula I.1. Such reductions can beperformed, for example, by means of zinc and ammonia and subsequentreaction with HCl/isopropanol, as is described, for example, in J. Org.Chem. 1980, 45, 1807-1817; J. Org. Chem. 1973, 38, 1167-1173; Bull.Chem. Soc. Jpn. 1971, 44, 1649-1652 and J. Am. Chem. Soc. 1969, 34,3089-3092. Compound III can also be converted into compound I.1 by, forexample, reaction of III with sodium borohydride and water (see T. R.Criswell et al., J. Org. Chem. 39 (1974), 770-774) or by reaction withaluminum alkoxides of cyclic alcohols, e.g. cyclohexanol, in thepresence of these alcohols (see M. W. Haenel et al., Chem. Ber. 124,1991, 333, and Fieser, Williamson, Organic Experiments, 3rd ed., 1975,p. 416ff. A suitable method of preparing 1,8-dichloroanthracene isdisclosed in H. House, J. Org. Chem. 1986, 51, 921-929. The disclosureof these references is hereby fully incorporated by reference.

[0109] Examples of suitable compounds of the formula III are compoundsof the formula III in which R¹, R², R³ and R⁴=hydrogen, and in which Yaand Yb are selected from among fluorine, chlorine, bromine, iodine,SO₃H, SO₃K, SO₃Na, OH, alkoxy such as methoxy or ethoxy. If two radicalsR² and R⁴ or R¹ and R³ are each an alkoxy group located in the orthoposition relative to Y^(a) or Y^(b), then Y^(a) and Y^(b) in III canalso be hydrogen.

[0110] To build up the basic bicyclo [2.2.2] framework, the compound ofthe formula I.1 can, as described above, be reacted with a suitabledienophile, preferably selected from among compounds of the formulaeII.a, II.b, II.c and II.d, according to scheme 2 below.

[0111] In the formula IV, F is a radical derived from a compound II.a toII.d after removal of an etheno or ethyno group. If an acetylenederivative II.a is used for the Diels-Alder reaction, compounds IV whichhave an etheno bridge (shown by the dotted double bond) are formed.

[0112] Suitable compounds of the formula II.a are, for example,acetylenedicarboxylic acid and its monoesters and diesters withC₁-C₈-monoalcohols.

[0113] Suitable compounds of the formula II.b are, for example, maleicacid, fumaric acid and their monoesters and diesters withC₁-C₈-monoalcohols.

[0114] The dehydroaromatics II.c and II.d are preferably prepared insitu from suitable precursors and used for the [4.2]-cycloaddition.Suitable starting materials and methods are described, for example, inCarey, Sundberg, Advanced Organic Chemistry, 2^(nd) edition, part B, p.402ff, Plenum Press, New York (1983), which is hereby incorporated byreference. The dehydroaromatics II.c and II.d are preferably prepared bydiazotization of the corresponding ortho-aminocarboxylic acids accordingto scheme 3 below.

[0115] The diazotization is preferably carried out using alkyl nitritessuch as n-butyl nitrite.

[0116] A suitable method of preparing 1,8-disubstitutedethanoanthracenes, e.g. 1,8-dichloroethanoanthracene, is described inJACS 94 (1972), pp. 3080-3088, which is hereby incorporated byreference.

[0117] The functionalization of the radicals Y^(a) and Y^(b) to form theradicals Y¹ and Y² can be carried out analogously to known methods. Forexample, compounds of the formula IV in which Y^(a) and Y^(b) arehalogen, preferably chlorine, can firstly be lithiated and theintermediate formed can be reacted with a compound bearing a halogenatom, preferably a chlorine atom, on the phosphorus atom, for example acompound of the formula Cl—P(R⁶)₂, Cl—P(R₆)(R₇) or Cl—P(R⁷)₂. Thecompounds I which are particularly preferred according to the presentinvention, in which R is a radical of the formula III with z=0, areprepared, for example by reacting IV with compounds of the formula Vaccording to scheme 4 below,

[0118] where x, y and D are as defined above for the compounds of theformula III.

[0119] In place of compounds of the formula IV in whichY^(a)═Y^(b)=halogen, it is also possible to lithiate compounds IV inwhich Y^(a)═Y^(b)=hydrogen and an alkoxy group or alkoxycarbonyl groupis located in each of the ortho positions relative to Y^(a) and Y^(b).Such reactions are referred to as “ortho lithiation” in the literature(cf., for example, D. W. Slocum, J. Org. Chem., 1976, 41, 3652-3654; J.M. Mallan, R. L. Bebb, Chem. Rev., 1969, 693ff; V. Snieckus, Chem. Rev.,1980, 6, 879-933). The organolithium compounds obtained in this way canthen be reacted with the phosphorus-halogen compounds in theabovementioned manner to give the target compounds I.

[0120] The preparation of the arsenic compounds and the antimonycompounds I can be carried out analogously.

[0121] Compounds of the formula IV in which Y^(a)═Y^(b)═OH can beconverted by sequential reaction with trifluoromethanesulfonic anhydridein the presence of a nitrogen base such as triethylamine andsubsequently with a phosphide of the formula MeP(R⁶)₂, where Me is Li,Na or K, into compounds of the formula I in which Y^(a)═Y^(b)═P(R⁶)₂.Here, R⁶ is selected from among those radicals mentioned above which areinert toward bases. MeP(R⁶)₂ is then, for example, KP(C₆H₅)₂. Thisreaction can be carried out in a manner analogous to the reactiondescribed by J. V. Allen et al. in Tetrahedron 50, 1994, p. 799-808.

[0122] Compounds IV in which Y^(a)═Y^(b)═SO₃K or═SO₃Na can be convertedby reaction with a phosphide of the formula MeP(R⁶)₂, where R⁶ isselected from among those radicals mentioned above which are inerttoward bases, and Me is Li, Na or K, for example with KP(C₆H₅)₂, intocompounds of the formula I in which Y^(a)═Y^(b)═P(R⁶)₂. This reactioncan be carried out in a manner analogous to the reactions described byM. W. Haenel, Chem. Ber. 124, 1991, p.333, or by H. Zorn, Chem. Ber. 98,1965, p. 2431.

[0123] Compounds of the formula IV in which Y^(a)═Y^(b)═F can beconverted into the corresponding diarylphosphines using a methodanalogous to the reaction described by Haenel in Synlett, 1988, 301-302.

[0124] The present invention further provides a catalyst comprising atleast one complex of a metal of transition group VIII with at least oneP-, As- or Sb-containing ligand selected from among compounds of theformula I, as described above.

[0125] The metal of transition group VIII is preferably selected fromamong cobalt, ruthenium, iridium, rhodium, nickel, palladium andplatinum.

[0126] The catalysts of the present invention can comprise one or moreof the phosphorus-containing compounds of the formula I. In addition tothe above-described ligands of the formula I, they can also have atleast one further ligand selected from among halides, amines,carboxylates, acetylacetonate, arylsulfonates and alkylsulfonates,hydride, CO, olefins, dienes, cycloolefins, nitrites, N-containingheterocycles, aromatics and heteroaromatics, ethers, PF₃, phospholes,phosphabenzenes and monodentate, bidentate and polydentate phosphine,phosphinite, phosphonite, phosphoramidite and phosphite ligands.

[0127] An object of the present invention is also to make available animproved process for the hydroformylation of compounds containing atleast one ethylenically unsaturated double bond. Here, a very highproportion of α-aldehydes or α-alcohols should preferably be achieved inthe hydroformylation of α-olefins. In particular, the process should besuitable for the hydroformylation of internal linear olefins with a highregioselectivity in respect of terminal product aldehydes.

[0128] The invention also provides a process for the hydroformylation ofcompounds containing at least one ethylenically unsaturated double bondby reaction with carbon monoxide and hydrogen in the presence of atleast one hydroformylation catalyst selected from among theabove-described catalysts of the present invention.

[0129] In general, the catalysts or catalyst precursors used in eachcase are converted under hydroformylation conditions into catalyticallyactive species of the formula H_(x)M_(y)(CO)_(z)L_(q), where M is ametal of transition group VIII, L is a phosphorus-containing compoundaccording to the present invention and q, x, y, z are integers whichdepend on the valence and type of the metal and on the number ofcoordination positions occupied by the ligand L. z and q are preferably,independently of one another, each at least 1, e.g. 1, 2 or 3. The sumof z and q is preferably from 2 to 5. If desired, the complexes canadditionally contain at least one of the further ligands describedabove.

[0130] The metal M is preferably cobalt, ruthenium, rhodium, nickel,palladium, platinum, osmium or iridium and particularly preferablycobalt, ruthenium, iridium, rhodium, nickel, palladium or platinum.

[0131] In a preferred embodiment, the hydroformylation catalysts areprepared in situ in the reactor used for the hydroformylation reaction.However, the catalysts of the present invention can also, if desired, beprepared separately and isolated by customary methods. For in-situpreparation of the catalysts of the present invention, it is possible,for example, to react at least one phosphorus-containing compound of theformula I, a compound or a complex of a metal of transition group VIII,if desired at least one further additional ligand and, if desired, anactivating agent in an inert solvent under the hydroformylationconditions.

[0132] Suitable rhodium compounds or complexes are, for example,rhodium(II) and rhodium(III) salts, e.g. rhodium(III) chloride,rhodium(III) nitrate, rhodium(III) sulfate, potassium rhodium sulfate,rhodium(II) or rhodium(III) carboxylates, rhodium(II) and rhodium(III)acetate, rhodium(III) oxide, salts of rhodic(III) acid, trisammoniumhexachlororhodate(III), etc. Also suitable are rhodium complexes such asdicarbonylrhodium acetylacetonate, acetylacetonatobisethylenerhodium(I),etc. Preference is given to using dicarbonylrhodium acetylacetonate orrhodiuim acetate. I

[0133] Likewise suitable are ruthenium salts or compounds. Suitableruthenium salts are, for example, ruthenium(III) chloride,ruthenium(IV), ruthenium(VI) or ruthenium(VIII) oxide, alkali metalsalts of oxo acids of ruthenium, e.g. K₂RuO₄ or KRuO₄, or complexes suchas RuHCl(CO)(PPh₃)₃. It is also possible to use metal carbonyls ofruthenium, e.g. dodecacarbonyltriruthenium oroctadecacarbonylhexaruthenium, or mixed forms in which CO is partlyreplaced by ligands of the formula PR₃, e.g. Ru(CO)₃(PPh₃)₂, in theprocess of the present invention.

[0134] Suitable cobalt compounds are, for example, cobalt(II) chloride,cobalt(II) sulfate, cobalt(II) carbonate, cobalt(II) nitrate, theiramine or hydrate complexes, cobalt carboxylates such as cobalt acetate,cobalt ethylhexanoate, cobalt naphthanoate, and also the cobaltcaprolactamate complex. Here too, the carbonyl complexes of cobalt, e.g.octacarbonyldicobalt, dodecacarbonyltetracobalt andhexadecacarbonylhexacobalt, can be used.

[0135] The abovementioned and further suitable compounds of cobalt,rhodium, ruthenium and iridium are known in principle and are adequatelydescribed in the literature or can be prepared by a person skilled inthe art using methods analogous to those for the known compounds.

[0136] Suitable activating agents are, for example, Brönsted acids,Lewis acids such as BF₃, AlCl₃, ZnCl₂, and Lewis bases.

[0137] As solvents, preference is given to using the aldehydes formed inthe hydroformylation of the respective olefins, and also theirhigher-boiling subsequent reaction products, e.g. the products of aldolcondensation. Other suitable solvents are aromatics such as toluene andxylenes, hydrocarbons or mixtures of hydrocarbons, also for dilution ofthe abovementioned aldehydes and subsequent products of the aldehydes.Further solvents are esters of aliphatic carboxylic acids with alkanols,for example ethyl acetate or Texanol™, ethers such as tert-butyl methylether and tetrahydrofuran. In the case of sufficiently hydrophilicligands, it is also possible to use alcohols, such as methanol, ethanol,n-propanol, isopropanol, n-butanol and isobutanol, and ketones such asacetone and methyl ethyl ketone, etc. Furthermore, “ionic liquids” canalso be used as solvents. These are liquid salts, for exampleN,N′-dialkylimidazolium salts such as N-butyl-N′-methylimidazoliumsalts, tetraalkylammonium salts such as tetra-n-butylammonium salts,N-alkylpyridinium salts such as n-butylpyridinium salts,tetraalkylphosphonium salts such as trishexyl(tetradecyl)phosphoniumsalts, e.g. the tetrafluoroborates, acetates, tetrachloroaluminates,hexafluorophosphates, chlorides and tosylates.

[0138] Furthermore, it is also possible to carry out the reactions inwater or aqueous solvent systems comprising water together with awater-miscible solvent, for example an alcohol such as methanol,ethanol, n-propanol, isopropanol, n-butanol or isobutanol, a ketone suchas acetone or methyl ethyl ketone or another solvent. For this purpose,use is made of ligands of the formula I which are modified with polargroups, for example ionic groups such as SO₃Me, CO₂Me where Me═Na, K orNH₄ or N(CH₃)₃ ⁺. The reactions then proceed in a two-phase catalyzedsystem in which the catalyst is present in the aqueous phase andstarting materials and products form the organic phase. The reaction inthe “ionic liquids” can also be carried out as a two-phase catalyzedsystem.

[0139] The molar ratio of the phosphorus-containing ligand to the metalof transition group VIII is generally in a range from about 1:1 to 1000:1.

[0140] Suitable substrates for the hydroformylation process of thepresent invention are in principle all compounds which contain one ormore ethylenically unsaturated double bonds. These include, for example,olefins such as α-olefins, internal straight-chain and internal branchedolefins. Suitable α-olefins are, for example, ethylene, propene,1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene,1-undecene, 1-dodecene, etc.

[0141] Preferred straight-chain internal olefins are C₄-C₂₀-olefins suchas 2-butene, 2-pentene, 2-hexene, 3-hexene, 2-heptene, 3-heptene,2-octene, 3-octene, 4-octene, etc.

[0142] Preferred branched, internal olefins are C₄-C₂₀-olefins such as2-methyl-2-butene, 2-methyl-2-pentene or 3-methyl-2-pentene, branched,internal heptene mixtures, branched, internal octene mixtures, branched,internal nonene mixtures, branched, internal decene mixtures, branched,internal undecene mixtures and branched, internal dodecene mixtures,etc.

[0143] Further olefins suitable for the hydroformylation process areC₅-C₈-cycloalkenes such as cyclopentene, cyclohexene, cycloheptene,cyclooctene and their derivatives, e.g. their C₁-C₂₀-alkyl derivativeshaving from 1 to 5 alkyl substituents. Vinylaromatics such as styrene,α-methylstyrene, 4-isobutylstyrene, etc., are also suitable olefins forthe hydroformylation process. Further suitable olefins forhydroformylation are α,β-ethylenically unsaturated monocarboxylic and/ordicarboxylic acids, their esters, monoesters and amides, e.g. acrylicacid, methacrylic acid, maleic acid, fumaric acid, crotonic acid,itaconic acid, methyl 3-pentenoate, methyl 4-pentenoate, methyl oleate,methyl acrylate, methyl methacrylate, unsaturated nitriles such as3-pentenenitrile, 4-pentenenitrile, acrylonitrile, vinyl ethers such asvinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, etc.,C₁-C₂₀-alkenols, -alkenediols and -alkadienols, e.g. 2,7-octadien-1-ol.A preferred alkenol is allyl alcohol. Further suitable substrates aredienes or polyenes having isolated or conjugated double bonds. Theseinclude, for example, 1,3-butadiene, 1,4-pentadiene, 1,5-hexadiene,1,6-heptadiene, 1,7-octadiene, vinylcyclohexene, dicyclopentadiene,1,5,9-cyclooctatriene and also homopolymers and copolymers of butadiene.

[0144] Preference is given to a process in which the hydroformylationcatalyst is prepared in situ by reacting at least one P-, As- orSb-containing compound according to the present invention, a compound ora complex of a metal of transition group VIII and, if desired, anactivating agent in an inert solvent under the hydroformylationconditions.

[0145] The hydroformylation reaction can be carried out continuously,semicontinuously or batchwise.

[0146] Suitable reactors for a continuous reaction are known to thoseskilled in the art and are described, for example, in UllmannsEnzyklopädie der technischen Chemie, vol. 1, 3^(rd) edition, 1951, p.743 ff.

[0147] Suitable pressure reactors are likewise known to those skilled inthe art and are described, for example, in Ullmanns Enzyklopädie dertechnischen Chemie, vol. 1, 3^(rd) edition, 1951, p. 769 ff. In general,the process of the present invention is carried out using an autoclavewhich may, if desired, be provided with a stirring device and internallining.

[0148] The composition of the synthesis gas, viz. a mixture of carbonmonoxide and hydrogen, used in the process of the present invention canvary within wide limits. The molar ratio of carbon monoxide to hydrogenis generally from about 5:95 to 70:30, preferably from about 40:60 to60:40. Particular preference is given to using a molar ratio of carbonmonoxide to hydrogen in the region of about 1:1.

[0149] The temperature in the hydroformylation reaction is generally ina range from about 20 to 180° C., preferably from about 50 to 150° C.The reaction is generally carried out at the partial pressure of thereaction gas at the chosen reaction tempereature. In general, thepressure is in a range from about 1 to 700 bar, preferably from 1 to 600bar, in particular from 1 to 300 bar. The reaction pressure can bevaried as a function of the activity of the hydroformylation catalyst ofthe present invention used. In general, the catalysts of the presentinvention based on phosphorus-containing compounds allow reaction atrelatively low pressures, for example from 1 to 100 bar.

[0150] The hydroformylation catalysts of the present invention can beseparated from the output from the hydroformylation reaction bycustomary methods known to those skilled in the art and can generally bereused for the hydroformylation.

[0151] Advantageously, the catalysts of the present invention display ahigh activity, so that the corresponding aldehydes are generallyobtained in good yields. In addition, in the hydroformylation ofα-olefins and of internal, linear olefins, they display a very lowselectivity to the hydrogenation product of the olefin used.Surprisingly, the hydroformylation activity of catalysts based oncompounds of the formula I is generally higher than the isomerizationactivity in respect of the formation of internal double bonds. In thehydroformylation of α-olefins, the catalysts of the present inventionadvantageously display a high selectivity to the α-aldehydes orα-alcohols. In addition, good yields of α-aldehdyes or α-alcohols andparticularly also n-aldehydes or n-alcohols are generally also obtainedin the hydroformylation of internal linear olefins (isomerizinghydroformylation).

[0152] The above-described, novel catalysts which comprise chiralcompounds of the formula I are suitable for enantioselectivehydroformylation.

[0153] The invention further provides for the use of catalystscomprising one of the above-described P-, As- or Sb-containing compoundsfor the hydroformylation of compounds having at least one ethylenicallyunsaturated double bond.

[0154] A further field of use for the catalysts of the present inventionis the hydrocyanation of olefins. The hydrocyanation catalysts of thepresent invention also comprise complexes of a metal of transititiongroup VIII, in particular cobalt, nickel, ruthenium, rhodium, palladium,platinum, preferably nickel, palladium and platinum and veryparticularly preferably nickel. The metal is generally present in themetal complex of the present invention in zero-valent form. Thepreparation of the metal complexes can be carried out as described abovefor use as hydroformylation catalysts. The same applies to the in-situpreparation of the hydrocyanation catalysts of the present invention.

[0155] An example of a nickel complex suitable for preparation of ahydrocyanation catalyst is bis(1,5-cyclooctadiene)nickel(0).

[0156] If desired, the hydrocyanation catalysts can be prepared in situin a manner analogous to the methods described for the hydroformylationcatalysts.

[0157] The present invention therefore also provides a process forpreparing nitriles by catalytic hydrocyanation, in which thehydrocyanation is carried out in the presence of at least one of theabove-described novel catalysts. Suitable olefins for hydrocyanation aregenerally the olefins mentioned above as starting materials forhydroformylation. A specific embodiment of the process of the presentinvention relates to the preparation of mixtures of monoolefinicC₅-mononitriles having nonconjugated C═C— and C≡N bonds by catalytichydrocyanation of 1,3-butadiene or 1,3-butadiene-containing hydrocarbonmixtures and isomerization/further reaction to form saturatedC₄-dinitriles, preferably adiponitrile, in the presence of at least onecatalyst according to the present invention. When hydrocarbon mixturesare used for preparing monoolefinic C₅-mononitriles by the process ofthe present invention, preference is given to using a hydrocarbonmixture which has a 1,3-butadiene content of at least 10% by volume,preferably at least 25% by volume, in particular at least 40% by volume.

[0158] 1,3-Butadiene-containing hydrocarbon mixtures are obtainable onan industrial scale. Thus, for example, the processing of petroleum bysteam cracking of naphtha produces a hydrocarbon mixture known as C₄fraction which has a high total olefin content of which about 40% ismade up by 1,3-butadiene and the remainder is made up of monoolefins andmultiply unsaturated hydrocarbons and also alkanes. These streams alwaysadditionally contain small proportions of generally up to 5% of alkynes,1,2-dienes and vinylacetylene.

[0159] Pure 1,3-butadiene can be isolated from industrially availablehydrocarbon mixtures by, for example, extractive distillation.

[0160] The catalysts of the present invention can advantageously be usedfor the hydrocyanation of such olefin-containing, in particular1,3-butadiene-containing, hydrocarbon mixtures, generally even withoutprior purification of the hydrocarbon mixture by distillation. Olefinswhich may possibly be present and reduce the effectiveness of thecatalysts, e.g. alkynes or cumulenes, may be removed from thehydrocarbon mixture by selective hydrogenation prior to thehydrocyanation. Suitable selective hydrogenation processes are known tothose skilled in the art.

[0161] The hydrocyanation of the present invention can be carried outcontinuously, semicontinuously or batchwise. Suitable reactors forcontinuous reaction are known to those skilled in the art and aredescribed, for example, in Ullmanns Enzyklopädie der technischen Chemie,volume 1, 3^(rd) edition, 1951, p. 743 ff. The continuous variant of theprocess of the present invention is preferably carried out using acascade of stirred vessels or a tube reactor. Suitable reactors, whichmay be pressure-rated, for the semicontinuous or continuous embodimentare known to those skilled in the art and are described, for example, inUllmanns Enzyklopädie der technischen Chemie, volume 1, 3^(rd) edition,1951, p. 769 ff. In general, the process of the present invention iscarried out using an autoclave which may, if desired, be provided with astirring device and internal lining.

[0162] The hydrocyanation catalysts of the present invention can beseparated from the output from the hydrocyanation reaction by customarymethods known to those skilled in the art and can generally be reusedfor the hydrocyanation.

[0163] The present invention further provides a process for thecarbonylation of compounds containing at least one ethylenicallyunsaturated double bond by reaction with carbon monoxide and at leastone compound having a nucleophilic group in the presence of acarbonylation catalyst, wherein the carbonylation catalyst used is acatalyst based on a P-, As- or Sb-containing ligand of the formula I.

[0164] The carbonylation catalysts of the present invention alsocomprise complexes of a metal of transition group VIII, preferablynickel, cobalt, iron, ruthenium, rhodium and palladium, in particularpalladium. The metal complexes can be prepared as described above in thecase of the hydroformylation catalysts and hydrocyanation catalysts. Thesame applies to the in-situ preparation of the carbonylation catalystsof the present invention.

[0165] Suitable olefins for the carbonylation are the olefins mentionedabove in general terms as starting materials for the hydroformylationand hydrocyanation.

[0166] The compounds having a nucleophilic group are preferably selectedfrom among water, alcohols, thiols, carboxylic esters, primary andsecondary amines.

[0167] A preferred carbonylation reaction is the conversion of olefinsinto carboxylic acids by reaction with carbon monoxide and water(hydrocarboxylation). This includes, in particular, the reaction ofethylene with carbon monoxide and water to give propionic acid.

[0168] The invention further provides for the use of catalystscomprising a P-, As- or Sb-containing compound according to the presentinvention, as described above, for hydroformylation, hydrocyanation,carbonylation, hydrogenation, oligomerization and polymerization ofolefins and for metathesis.

[0169] The invention is illustrated by the following, nonlimitingexamples.

EXAMPLES

[0170] I. Preparation of Compounds I

Example 1 1,8-Bis(diphenylphosphino)triptycene(=1,8-bis(diphenylphosphino)-9,10-dihydro-9,10-benzoanthracene) (LigandA)

[0171] 1.1 Preparation of 1,8-dichloroanthracene

[0172] 25 g (91 mmol) of 1,8-dichloroanthraquinone and 65 g (1 mol) ofZn dust were suspended in 1 l of a 20% strength by weight aqueousammonia solution and the mixture was refluxed for 3 hours. After coolingto room temperature, the solid was separated off via a Büchner funnel.The aqueous phase was extracted three times with 150 ml each time ofdichloromethane; the solid was extracted a number of times withdichloromethane while being treated with ultrasound. The combinedorganic phases were dried over magnesium sulfate and freed of thesolvent on a rotary evaporator. The solid, whitish yellow residue wassuspended in 600 ml of propanol and 65 ml of 12M hydrochloric acid andthe mixture was refluxed for three hours. The solvent was subsequentlyremoved under reduced pressure, the residue was taken up indichloromethane, the solution was washed with saturated sodium hydrogencarbonate solution and dried over magnesium sulfate. Removal of thesolvent gave 1,8-dichloroanthracene as a yellow solid which wasrecrystallized from propanol.

[0173] Yield: 9.4 g (38 mmol)=42% of theory.

[0174] Melting point: 155° C. (literature: 156-158° C.)

[0175] 1.2 Preparation of 1,8-dichlorotriptycene

[0176] 6.97 g (28 mmol) of 1,8-dichloroanthracene were suspended in 120ml of 1,2-dichloroethane and the mixture was heated to reflux. 3.2 g (31mmol) of n-butyl nitrite were added to the yellow solution, and asolution of 4 g (29 mmol) of anthranilic acid in 25 ml of 2-ethoxyethylether was added dropwise to the resulting mixture. After half an hour,the solvent was distilled from the black solution until the temperatureat the distillation head was 150° C. After addition of 2 g (20 mmol) ofmaleic anhydride, the mixture was refluxed for three minutes,subsequently cooled by means of an icebath and a solution of 67 ml ofmethanol, 34.4 ml of water and 8 g of potassium hydroxide was thenadded. The brown solid was filtered off and washed with methanol:waterin a ratio of 4:1 until the washings were colorless. The flesh-coloredsolid was dissolved in 2-butanone, admixed with 200 mg of activatedcarbon and this mixture was refluxed for one hour. After filtering offthe activated carbon, the clear solution was concentrated by evaporationand the product was allowed to crystallize in a refrigerator. Additionof methanol resulted in crystallization of further product. The productcan be recrystallized from 2-butanone.

[0177] Yield: 5.61 mg (17 mmol)=62%

[0178] Melting point: 297° C. (literature: 299.5-300° C.)

[0179] 1.3 Preparation of 1,8-bis(diphenylphosphino)triptycene

[0180] All steps were carried out with exclusion of oxygen and water ina protective argon gas atmosphere.

[0181] A solution of 485 mg (1.5 mmol) of9,10-benzo-1,8-dichloro-9,10-dihydroanthracene in 20 ml oftetrahydrofuran was added dropwise over the course of one hour to asuspension of 82 mg (12 mmol) of lithium powder in 10 ml oftetrahydrofuran which had been cooled to −78° C. The resulting redsuspension was kept at −78° C. for a further seven hours, after which772 mg (3.5 mmol) of diphenylchlorophosphine were added to the filtrate,cooling was removed and the yellow solution was stirred at roomtemperature for four hours. After removal of all the solvent underreduced pressure, the remaining solid was admixed with water andextracted with dichloromethane. The solvent phase was dried overmagnesium sulfate. After removal of the dichloromethane under reducedpressure, the product was recrystallized from toluene.

[0182] Yield: 392 mg (0.63 mmol)=42%

[0183] Characterization:

[0184]³¹P-NMR (CDCl₃, 121.495 MHz, 300K): δ=−14.7

[0185]¹H-NMR (C₆D₆, 300.132 MHz, 300K): δ=5.20 (s, 1H, H10), 6.18 (s,1H, H9), 6.62-7.34 (m, H—Ar)

[0186]¹³C-NMR (CDCl₃, 75.469 MHz, 300K): δ=29.7 (C10), 59.0 (C9),122.7-145.6 (C—Ar)

Example 2 1,8-Bis(diphenylphosphino)-9,10-ethanoanthracene (Ligand B)

[0187] 2.1 The preparation of 1,8-dichloroanthracene was carried out asdescribed in 1.1.

[0188] 2.2 1,8-Dichloranthracene was reacted with ethene in aDiels-Alder reaction to a give1,8-dichloro-9,10-dihydro-9,10-ethanoanthracene, using the method inJACS 94(9) (1972), pp. 3080-3088.

[0189] 2.3 The preparation of1,8-bis(diphenylphosphino)-9,10-dihydro-9,10-ethanoanthracene wascarried out by lithiation and reaction with diphenylchlorophosphane, asdescribed in 1.3.

[0190] II Examination of the Catalytic Action of Transition MetalComplexes with Ligands of the Formula I

Example 3

[0191] 1.6 mg of dicarbonylrhodium(II) 2,4-pentanedionate (Rh(CO)₂acac)and 19 mg of 1,8-bis(diphenylphosphino)triptycene (ligand A,ligand:metal ratio=5:1 mol/mol) were dissolved in 5 ml of toluene andsubsequently heated at 100° C. for 30 minutes under a synthesis gaspressure of 10 bar (H₂/CO atmosphere having a molar ratio of 1:1) in anautoclave. 5 g of 1-octene were then added, a synthesis gas pressure of5 bar was set and the temperature was held for 4 hours. The reactionproduct was analyzed by gas chromatography. The conversion based on1-octene used was 43%. The selectivity to the formation of nonanal was92%. The proportion of n-nonanal was 99.2%.

Example 4

[0192] 1.6 mg of dicarbonylrhodium acetylacetonate and 57 mg of ligand A(ligand-metal ratio=15:1) were dissolved in 5 g of toluene andsubsequently heated at 100° C. for 30 minutes under a CO/H₂ (1:1)pressure of 10 bar in a glass autoclave. 5 g of 1-octene weresubsequently added and a synthesis gas pressure of 10 bar was set for 4hours. Analysis of the reaction product showed a conversion of 1-octeneof 77% with an aldehyde selectivity of 98% and a linearity of 99%. Theproportion of α-aldehyde was 100%.

Example 5

[0193] 1.6 mg of dicarbonylrhodium acetylacetonate, 76 mg of ligand Aand 16 mg of triphenylphosphine (triptyphos:triphenylphosphine:rhodiumratio=20:10:1) were dissolved in 5 g of toluene and subsequently heatedat 100° C. for 30 minutes under a CO/H₂ (1:1) pressure of 10 bar in aglass autoclave. 5 g of 1-octene were subsequently added, the mixturewas heated to 120° C. and a synthesis gas pressure of 10 bar was set for4 hours. Analysis of the reaction product showed a conversion of1-octene of 97% with an aldehyde selectivity of 92% and a linearity of99%. The proportion of α-aldehyde was 100%.

Example 6

[0194] 5.42 mg of dicarbonylrhodium acetylacetonate and 181.3 mg ofligand B were separately dissolved in 5.5 g each of diphenyl ether,combined and preactivated at 100° C. for 30 minutes under a synthesisgas pressure (CO:H₂=1:1) of 10 bar. 11 g of 1-octene (purity: 97% of1-octen; remainder: internal octenes) were subsequently added by meansof a lock, and the mixture was hydroformylated at 100° C. and 10 bar for4 hours. Analysis of the reaction product by means of gas chromatographyindicated a conversion of 1-octene of 98%. The aldehyde selectivity was96%, the proportion of n-aldehyde was 99% and the proprotion ofα-aldehyde (n-aldehyde and iso-aldehyde) was 100%.

[0195] It can be seen from this that use of the novel catalysts enablesterminal olefins to be converted into terminal aldehydes with highlinearity and very good activity and at the same time with minimalisomerization to internal olefins.

1. A compound of the formula I

where A¹ and A² are each, independently of one another, B, N, P or CR⁵,where R⁵ is hydrogen, alkyl, cycloalkyl, aryl or heteroaryl, X is O, S,NR^(a) or a divalent bridging group, where R^(a) is hydrogen, alkyl,cycloalkyl or aryl, Y¹ and Y² are, independently of one another,radicals containing at least one phosphorus, arsenic or antimony atom,where the phosphorus, arsenic or antimony atom is bound directly or viaan oxygen atom to the phenyl ring in formula I, R¹, R², R³ and R⁴ areeach, independently of one another, hydrogen, alkyl, cycloalkyl, aryl,alkoxy, halogen, NE¹E², alkylene-NE¹E², trifluoromethyl, nitro,alkoxycarbonyl or cyano, where E¹ and E² are identical or different andare each alkyl, cycloalkyl or aryl.
 2. A compound of the formula I asdefined in claim 1 in which A¹ and/or A² are/is CR⁵, where R⁵ is apolymeric support which may be bound via a spacer group.
 3. A compoundas claimed in either of the preceding claims, wherein Y¹ and Y² areeach, independently of one another, a radical of the formula PR⁶R⁷,P(OR⁶)R⁷, P(OR⁶)(OR⁷), OPR⁶R⁷, OP (OR⁶)R⁷ or OP(OR⁶)(OR⁷), where R⁶ andR⁷ are each, independently of one another, alkyl, cycloalkyl, aryl orheteroaryl which may bear one, two or three substituents selected fromamong alkyl, cycloalkyl, aryl, alkoxy, cycloalkyloxy, aryloxy, halogen,trifluoromethyl, nitro, cyano, carboxyl, carboxylate, acyl, SO₃H,sulfonate, NE¹E² and alkylene-NE¹E², where E¹ end E² are as definedabove, or R⁶ and R⁷ together with the phosphorus atom and, if present,the oxygen atom(s) to which they are bound form a 5- to 8-memberedheterocycle which may additionally be fused with one, two or threecycloalkyl, aryl and/or heteroaryl rings, where the fused-on groups mayeach bear, independently of one another, one, two, three or foursubstituents selected from among alkyl, alkoxy, halogen, SO₃H,sulfonate, NE¹E², alkylene-NE¹E², nitro, cyano, carboxyl and carboxylateand where the heterocycle may additionally contain one or twoheteroatoms(s) selected from among N, O and S.
 4. A compound as claimedin any of the preceding claims, wherein X is a C₁-C₁₀-alkylene bridgewhich may contain one, two, three or four double bonds and/or may bearone, two, three or four substituents selected from among alkyl, alkoxy,halogen, nitro, cyano, carboxyl, carboxylate, cycloalkyl and aryl, wherethe aryl substituent may additionally bear one, two or threesubstituents selected from among alkyl, alkoxy, halogen, SO₃H,sulfonate, NE¹E², alkylene-NE¹E², trifluoromethyl, nitro, alkoxycarbonyland cyano, and/or the alkylene bridge X may be interrupted by one, twoor three nonadjacent, substituted or unsubstituted heteroatoms, and/orthe alkylene bridge X may be fused with one, two or three aryl and/orheteroaryl rings, where the fused-on aryl and heteroaryl groups may eachbear one, two or three substituents selected from among alkyl,cycloalkyl, aryl, alkoxy, cycloalkoxy, aryloxy, acyl, halogen, SO₃H,sulfonate, trifluoromethyl, nitro, cyano, carboxyl, alkoxycarbonyl,NE¹E² and alkylene-NE¹E², where E¹ and E² may be identical or differentand are each alkyl, cycloalkyl or aryl.
 5. A compound as claimed inclaim 4, wherein X is selected from among radicals of the formulae II.1to II.10

where Z is O, S or NR¹⁶, where R¹⁶ is alkyl, cycloalkyl or aryl, or Z isa C₁-C₃-alkylene bridge which may contain a double bond and/or bear analkyl, cycloalkyl or aryl substituent, where the aryl substituent maybear one, two or three substituents selected from among alkyl, alkoxy,halogen, SO₃H, sulfonate, NE¹E², alkylene-NE¹E², trifluoromethyl, nitro,alkoxycarbonyl and cyano, or Z is a C₂-C₃-alkylene bridge which isinterrupted by O, S or NR¹⁶, R⁸, R⁸′, R⁹, R⁹′, R¹⁰, R¹¹, R¹², R¹³, R¹⁴and R¹⁵ are each, independently of one another, hydrogen, alkyl,cycloalkyl, aryl, alkoxy, halogen, SO₃H, sulfonate, NE¹E²,alkylene-NE¹E², trifluoromethyl, nitro, alkoxycarbonyl, carboxyl orcyano.
 6. A compound as claimed in any of claims 3 to 5, wherein R⁶ andR⁷ together with the phosphorus atom and, if present, the oxygen atom(s)to which they are bound form a 5- to 8-membered heterocycle, where R⁶and R⁷ are together a radical selected from among the radicals II.5 toII.9 as defined in claim
 5. 7. A compound as claimed in any of thepreceding claims which is selected from among compounds of the formulaeI.i to I.v

where R^(a) is selected from among C₁-C₆-alkyl, C₁-C₆-alkoxy,C₅-C₇-cycloalkoxy, phenyl, phenoxy and pentafluorophenyl, where thephenyl- and phenoxy radicals may bear a substituent selected from amongcarboxyl, carboxylate, —SO₃H and sulfonate, R^(b), R^(b)′, R^(c) andR^(c)′ are selected independently from among hydrogen, C₁-C₆-alkyl,C₁-C₆-alkoxy, C₁-C₆-alkoxycarbonyl and aryl, R^(d) and R^(e) areselected independently from among hydrogen and C₁-C₆-alkyl, R^(f) andR^(g) are selected independently from among hydrogen, C₁-C₆-alkyl andC₁-C₆-alkoxy, and A¹ and A² are each, independently of one another, N orCR⁵, where R⁵ is hydrogen or C₁-C₈-alkyl.
 8. A process for preparing acompound of the formula I in which X is a radical of the formulae II.1,II.2, II.3 or II.4

R⁸, R⁸′, R⁹, R⁹′, R¹⁰ and R¹¹ are each, independently of one another,hydrogen, alkyl, cycloalkyl, aryl, alkoxy, halogen, SO₃H, sulfonate,NE¹E², alkylene-NE¹E², trifluoromethyl, nitro, alkoxycarbonyl, carboxylor cyano, by reacting a compound of the formula I.1

where A¹ and A² are each, independently of one another, B, N, P or CR⁵,where R⁵ is hydrogen, alkyl, cycloalkyl, aryl, heteroaryl or a polymericsupport which may be bound via a spacer group, Y^(a) and Y^(b) are each,independently of one another, radicals Y¹ or Y² as defined in claim 1,or Y^(a) and Y^(b) are each, independently of one another, halogen, OH,OC(O)CF₃ or SO₃Me where Me=hydrogen, Li, Na or K, where Y^(a) and/orY^(b) can also be hydrogen if in each case one of the radicals R² and/orR⁴ is an alkoxy group which is located in the ortho position of Y^(a)and/or Y^(b), R¹, R², R³ and R⁴ are each, independently of one another,hydrogen, alkyl, cycloalkyl, aryl, alkoxy, halogen, SO₃H, sulfonate,NE¹E², alkylene-NE¹E², trifluoromethyl, nitro, alkoxycarbonyl or cyano,with a compound selected from among compounds of the formulae II.a,II.b, II.c or II.d

(II.a) (II.b) (II.c) (II.d) or a precursor of a compound of the formulaII.c or II.d in a [4+2]-cycloaddition (Diels-Alder reaction) andfunctionalizing radicals Y^(a) and/or Y^(b) to form radicals Y¹ and/orY².
 9. A catalyst comprising at least one complex of a metal oftransition group VIII with at least one ligand selected from amongcompounds of the formula I as defined in any of claims 1 to
 7. 10. Acatalyst as claimed in claim 9, wherein the metal of transition groupVIII is selected from among cobalt, ruthenium, iridium, rhodium, nickel,palladium and platinum.
 11. A catalyst as claimed in claim 9 or 10 whichfurther comprises at least one additional ligand selected from amonghalides, amines, carboxylates, acetylacetonate, arylsulfonates andalkylsulfonates, hydride, CO, olefins, dienes, cycloolefins, nitriles,N-containing heterocycles, aromatics and heteroaromatics, ethers, PF₃,phospholes, phosphabenzenes and monodentate, bidentate and polydentatephosphine, phosphinite, phosphonite, phosphoramidite and phosphiteligands.
 12. A process for the hydroformylation of compounds containingat least one ethylenically unsaturated double bond by reaction withcarbon monoxide and hydrogen in the presence of a catalyst as claimed inany of claims 9 to 11 as hydroformylation catalyst.
 13. A process forthe hydrocyanation of compounds containing at least one ethylenicallyunsaturated double bond by reaction with hydrogen cyanide in thepresence of a catalyst as claimed in any of claims 9 to 11 ashydrocyanation catalyst.
 14. A process as claimed in claim 12 or 13,wherein the hydroformylation catalyst or the hydrocyanation catalyst isprepared in situ by reacting at least one compound of the formula I asdefined in any of claims 1 to 7, a compound or complex of a metal oftransition group VIII and, if desired, an activating agent in an inertsolvent under the hydroformylation conditions or hydrocyanationconditions.
 15. A process for the carbonylation of compounds whichcontain at least one ethylenically unsaturated double bond by reactionwith carbon monoxide and at least one compound containing a nucleophilicgroup in the presence of a catalyst as claimed in any of claims 9 to 11as carbonylation catalyst.
 16. The use of a catalyst comprising at leastone compound of the formula I as claimed in any of claims 1 to 7 forhydroformylation, hydrocyanation, carbonylation, hydrogenation, olefinoligomerization and olefin polymerization and for metathesis.